1. Technical Field of the Invention
The disclosure relates to a computer application technique; in particular, to a computing device which detects the connection status of a connection module, in order to determine whether to provide electric power.
2. Description of the Related Art
When the computer system (for example, a desktop computer, a notebook computer, or an all-in-one computer) including universal serial bus (USB) connection ports enters a shutdown mode or a sleep mode, the chip sets (for example, a south bridge chip set) in the computer system still provide power (for example, a 5V voltage) to the USB connection ports, for sensing the input signals transmitted by the peripheral devices, such as a mouse, a keyboard, or some external human interface devices (HID). That is, the peripheral devices can receive a power supply from the computer system through the USB connection ports, no matter what mode the computer system is under. For example, when the computer system is in the shutdown mode or the sleep mode, the USB connection ports still continuously provide electric power to the HID devices such as the mouse and the keyboard, thus the user can turn on or make the computer system recover to the normal mode by triggering the mouse or pushing the specific button on the keyboard via the USB connection ports.
However, the disadvantage of the above manners is that the computer system needs to provide electric power to each of the USB connection ports no matter if the computer system is in the shutdown mode or the standby mode, thus the electric power is wasted. For example, when the computer system is in the sleep mode, each USB connection port still consumes 500 microamperes (μA, low power devices) or 2.5 milliamperes (mA, high power devices) of electric currents, that means respectively consuming 2500 μW or 12.5 mW of the electric power. Moreover, the conventional computer system has a plurality of USB connection ports, which makes small power consumptions be accumulated into large power consumption. In addition, the computer system usually does not have the relating mechanisms for detecting whether each of the USB connection ports is connected to a corresponding human interface device (HID). That is, the computer system cannot know connection statuses of the USB connection ports, thus the south bridge chips can only provide electric power to all of the USB connection ports. Therefore, the unused USB connection ports of the computer system still consume unnecessary electric power.